Observation of the second proton alignment in Tm160

High-spin states in the doubly odd nucleus Tm-160 have been investigated using the Te-130(Cl-35,5n) reaction and the Euroball gamma-ray detector array. The previously established rotational structures in Tm-160 were extended, leading to the first observation of the second (h(11/2))(2) proton band crossing in this nucleus. This crossing is found to occur at a higher rotational frequency in Tm-160 than in lighter Tm isotopes. This trend resembles that of the first (h(11/2))(2) proton band crossing found in neighboring Er nuclei and is associated with a predicted increase in deformation as a function of neutron number in these isotopes.